Electric motor-driven agitator



2 Sheets-Sheet l Filed March 15, 1949 IN VEN TOR.

May 8, 1951 R. H. ANDRESEN ELECTRIC MOTOR-DRIVEN AGITATOR 2 Sheets-Sheet 2 Filed March 15, 1949 INVENTOR. iayfizaizdflfizzdreaen,

Patented May 8, 1951 ELECTRIC MOTOR-DRIVEN AGITATOR Raymond H. Andresen, Chicago, Ill., assignor to Edgar J. Schoen and Herbert J. Schoen, both of Chicago, 111.

Application March 15, 1949, Serial No. 81,555

Claims.

This invention is concerned with improvements in a food mixer.

It is an object of the invention to provide a food mixer of the portable hand manipulated type which is simple, compact, light in weight, of rugged construction and which will operate efficiently to mix various kinds of materials having varying viscosities.

A more specific object of the invention is to provide a food mixer comprising a casing having enclosed therein a light compact driving motor and bearing supporting structures mounted axially of the motor shaft and providing at opposite ends of the casing compartments for housing a speed controlling device and driving gears, respectively, the driving gears being adapted to rotate in opposite directions concentrically mounted beater shafts, and the compartment housing the driving gears being closed bya plate on which the gears and the drive mechanism connecting the gears with the beater shafts are supported.

A further object of the invention is to provide a food mixer of the type described in which a driving motor, a Cooling fan, a speed regulating and control mechanism and gear mechanism for driving concentrically arranged beater shafts are operatively associated by supporting structures which are adapted to be readily assembled and disassembled to provide greater economy in manufacture and more convenient repair and maintenance.

It is another object of the invention to provide in a food mixer construction a driving motor and a driving mechanism for concentrically arranged beater shafts which provide vibrationless operation of the beater shafts.

It is a further object of the invention to provide in a food mixer a driving motor, a regulator and control device for varying the speed of the motor, and a gear driving mechanism for concentrically arranged beater shafts.

It is another object of the invention to provide in a food mixer of the type described a driving motor, a gear mechanism for driving concentrically arranged beater shafts and connecting mechanism between the driving gears and the beater shafts providing for ready release of the shafts from the gear mechanism.

These and other objects and advantages will be apparent from a description of the preferred form of the food mixer which is shown by way of illustration in the accompanying drawings, wherein:

Fig. 1 is a side elevation of a food mixer embodying the principles of the invention with the greater portion thereof shown in longitudinal section;

Fig. 2 is a partial front elevation of the upper portion of the mixer casing with portions broken away;

Fig. 3 is a section on the line 33 of Fig. 1;

Fig. 4 is a section on the line 4-4 of Fig. 1;

Fig. 5 is a section on the line 5--5 of Fig. 1;

Fig. 6 is a bottom plan view; and

Fig. 7 is a fragmentary elevation of the lower portion of the mixer with portions broken away.

Referring to the drawings, the mixer construction comprises a casing or housing [0 which is adapted to enclose a driving motor ll, gear mechanism 12 at one end of the motor shaft connecting the motor in driving relation to the inner ends of concentric beater shafts 13, I4 and a motor control mechanism [5 arranged in the casing It at the opposite end of the motor shaft for controlling the speed of operation of the motor I l.

The casing l0 includes two sections l6 and I! which are connected together when the mixer is assembled, the sections being connected by bolts 18 extending through the transverse web [9 in the casing section It and engaging in screwthreaded relation in sockets 26 in the casing section H. The connecting bolts 18 extend through apertured portions of the body or laminated stator core 2| of the motor II and secure the motor I l in rigid relation in the casing The outer end of the casing section I1 is offset in an axial direction and provided with compartment 22 for accommodating the driving gears l2. The compartment 22 is separated from the main portion of the section ll by a transverse web 23 which is apertured at 24 and provided with a bearing or bushing member 25. The bearing member 25 receives in rotatable relation a sleeve 26 which is secured to the projecting end 21 of the motor drive shaft. The sleeve 26 carries a fan construction 28. The end 27 of the motor shaft is keyed to a stub shaft 2E which carries on its outer end a gear or pinion 39. The pinion 30 engages between an outer ring gear 31 and an inner spur gear 32. The pinion Si is in driving relation with gears 3| and 32 so that upon rotation of the motor drive shaft the gears 3| and 32 are driven in opposite directions.

The outer ring gear 3| is mountedv in a holder or supporting member 33 which is provided with a hub 34. An outer sleeve 35 is secured at one end to the hub '34 and. extends therefrom a substantial distance, being secured to the enlarged portion of a driving sleeve 36. The other end of the driving sleeve 36 is reduced somewhat at 31 to fit within the end of the outer tubular beater shaft M. A spring catch 38 is provided between the outer sleeve portion 3! and the end of the shaft 55 to releasably hold the members in driving relation. The ring gear holder 33 and outer sleeve 55 are rotatably mounted in an Oilite bearing 35 which is secured in a central aperture in the cover plate Lit which closes the compartment 32 on the casing section I! and which is removably secured thereto by screws ll or other fastening means.

ihe spur gear 52 is provided with an outwardly extending shaft 52 which projects through the hub portion 55 of the bearing holder 33 and into the reduced portion 3'! of the outer spindle 36 being rotatably supported therein by an Oilite bearing 55, against the end of which shoulder or flange bears. The shaft $2 is provided with an outwardly opening axial socket 45 for receiving the end of the inner beater shaft i3 which is releasably held therein by fastener rings 56.

The spur gear 32 is separated from the transverse web 23 of the casing section H by a thrust bearing ii in axial alignment with the shaft i2.

The cover plate it carries a releasing device for separating the beater shafts from the driving connector members '31 and. G2. The releasing device comprises a cap-like member 58 which includes a tubular inner portion 59 embracing the hub 55 of the plate at and having an inner flange which seats against the face of the plate '48 in the retracted position. A coil compression spring 52 bears against the flange 5i and is retained in a ring-like casing 55 which is secured by screws as to the outer face of the plate 45. At its outer end the cap member '58 is provided with an internal cam surface '55 which engages the cam formation 55 on the outer edge of the hub 55. The member :18 is provided with a finger gripping piece 51 by means of which it may be rotated relative to the hub ac. Movement of the finger piece 5'1 is limited by a pair of spaced stop pins i 53 on the spring casing 53. The member 18 is provided at its outer end with an inwardly ex tending shoulder 55 which engages the inner end of the beater shaft It. When the member d3 is rotated by the finger piece 5i the cam surfaces and 55 cause the member 48 to move outwardly relative to the hub 50 and force the beater shafts l3 and id outwardly to release them from the retaining springs 38 and Q6.

The casing section It is provided with peripherally spaced socket formations 6!} for receiving the brushes 5i for the motor H which are held in engaging position by the springs 62 and cap screws 53.

The speed control device l5 comprises a circular plate member M which is secured to the end 55 of the motor shaft and which includes contact rings 65, El on the bottom surface thereof. Spring-pressed brushes 68, '89 are mounted in the transverse web portion id of section it on opposite sides of the bearing is which supports the motor shaft end 55 and engage the respective rings 66, Bl. The brushes 58, 69 are insulated from the web portion ['9 and are electrically connected to the current supply. The rings 56 and iii are connected to the arm elements H and 12 of a breaker switch (Fig. 4) provided on "the upper face of the plate 64. The arm members H and I2 carry at their outer ends conventional contact members and are spring urged toward each other.

A control for the contact members on the arms H and 72 is provided which comprises transversely extending rod 13 which projects through an aperture in the arm 12 and is headed so that predetermined movement of the rod 13 in a direction away from the arm 12 exerts a pull on the arm 72 and permits separation of the contact points on the arms H and '12 by centrifugal force at a lower speed. At the other end the rod 13 is pivoted to a bent arm 1-4 of an angular plate member 15 which is pivotally mounted on the plate 6'4 at 16. y The free end of the plate 75 is adapted to be engaged by a pin 11 which projects downwardly through a transverse plate 18 and which is slidably mounted in an upwardly extending hub 19 on the plate 18 and which is provided With a cross pin 8!) at the top end thereof. The cross pin 8%] extends out over the hub 19 and is urged in an outward direction by a compression spring 8!. The hub '79 is provided with aligned slots 82 to permit a limited movement of the pin ll. When the pin 11 is moved downward against the operation of the spring 8! the arm 15 of plate member 15 is depressed and moves the rod 13 in the direction away from the switch arm l2.

The transverse plate 18 is supported on downwardly directed bracket members M which are secured by the screws 85 to the wall of the casing section it. An end cap 56 is secured in rotatable relation on the plate "it by means of a spring wire fastener '81. The cap 85 carries a downwardly projecting pin t8 movable in a socket 89 and backed by a compression spring 95. The lower end of the pin 88 selectively engages in depressions or pockets 9| (Fig. 3) circumferentially spaced on the top surface of the plate 18 to provide an indexing means. In the center of the cap 86 a cam 92 is secured by a screw 93 and provided with a spiral edge 96 which engages the cross pin *85 and upon rotation of the cap 85 controls the position of the pin H.

The casing sections IE and H are provided with slots 55 at their respective opposite end for circulating air by operation of the fan 28. At one side corresponding to the offset portion of the section I? the section it is provided with a handle member 95 which houses part of the lectrical connections for supplying current to the motor I l.

The operation of the mixer will be obvious from the detailed description of the parts. The current supplied to the motor is controlled by rotating the end cap 86. The concentric beater shafts l3 and IG- are driven from the motor shaft 2'! through the gear arrangement. When it is desired to remove the beater elements from the mixer the finger piece 57 is rotated to cause the member 48 to move outwardly by engagement of cam surfaces 55 and 56. Movement of the shoulder 59 against the end of shaft l4 forces the shafts l3 and id to move outwardly and disengages latching rings 38 and d5 permittin bodily removal of the shafts l3 and M.

While specific details of construction have been referred to in describing the illustrated form of the mixer, it will be understood that other details of construction may be resorted to within the scope of the invention.

I claim:

1. In a motor driven foodmixer, a casing comprising complementary motor enclosing sections having transverse web portions at opposite ends and bearings in said Web portions supporting the motor drive shaft, one of said casing sections having a portion extending in axially offset relation beyond the transverse web in said section and providing an outwardly opening compartment, an end plate adapted to be positioned on the end of said casing section to close said compartment, concentric inner and outer beater shaft connecting members journaled in said end plate and extending into said compartment in axial offset relation to said motor drive shaft, concentric gear members including an outer ring gear and an inner spur gear secured on the inner ends of said connecting members, and a gear secured on the end of said motor drive shaft engaging between said concentric gear members in driving relation to rotate said beater shaft connecting members in opposite directions.

2. In a motor driven food mixer, a casing comprising complementary motor enclosing sections having transverse web portions at opposite ends and bearings in said web portion supporting the motor drive shaft, one of said casing sections having a portion extending in axially offset relation beyond the transverse web in said section and providing an outwardly opening compartment, an

end plate adapted to be positioned on the end of said casing section to close said compartment, inner and outer concentric beater haft connecting members having the inner ends thereof journaled in said end plate and extending into said compartment in axial offset relation to the motor drive shaft, concentric outer ring and inner spur gear members secured on the inner ends of said beater shaft connectin members, a pinion secured in readily separable relation on the end of said motor drive shaft engaging between said concentric gear members in driving relation to rotate said beater shaft connecting members in opposite directions and a thrust bearing between said concentric gear members and the adjacent transverse web in the casing.

3. In a motor driven food mixer, a motor enclosing casing comprising complementary sections provided with transversely extending bearing support members at opposite ends thereof, a motor secured in said casing sections and having the ends of the drive shaft mounted in bearings in said support members, concentric shaft connecting members journaled in the outer end of one of the casing sections in offset relation to the motor drive shaft, said connecting members being adapted to be detachably connected to the ends of concentric beater shafts, cooperating concentric ears mounted in driving relation between the motor shaft and said connecting members, and a beater shaft releasing device mounted on said casing for engaging said beater shafts to disconnect the same from said connecting members.

4. In a motor driven food mixer having a casing, a motor mounted in said casing, a gear mechanism in said casing connected to one end of the motor drive shaft, and connector members at the end of said casing for detachable engagement with concentric beater shafts and having driving connection with said gear mechanism, a beater shaft releasing mechanism comprising a hub portion on said casing having a cam surface at the outer end, a spring pressed cap member encompassing said hub portion in rotatable relation, said cap member having an internal cam surface coopearting with the cam surface on said hub portion when said cap member is rotated to cause said cap member to move outwardly and said cap member having an abutment shoulder engaging the end of one of said beater shafts whereby movement of the cap member outwardly disengages the beater shafts from said connector members.

5. In a motor driven agitator having a casing, a motor mounted in said casing, a gear mechanism in said casing connected to one end of the motor drive shaft, and connector members on said casing for detachable engagement with concentric beater shaft and. having driving connection with said gear mechanism, a beater shaft releasing mechanism comprising a portion on said casing having a cam surface at the outer end, a spring-pressed cap member encompassing said cam surface portion in rotatable relation thereto, said cap member having an internal cam surface portion cooperating with said first mentioned cam surface portion when said cap member is rotated to cause said cap member to move outwardly, and cooperating abutment forming portions on said cap member and the outer one of said beater shafts whereby movement'of the cap member outwardly disengages the beater shafts from said connector members.

RAYMOND H. ANDRESEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 512,258 Murrey Jan. 2, 1894 675,709 Blum June 4, 1901 1,411,539 Sweetland Apr. 4, 1922 1,424,879 Carlstedt Aug. 8,-1922 1,939,399 Larsh Dec. 12, 1933 2,192,845 Bean Mar. 5, 1940 2,209,287 Simpson July 23, 1940 2,292,566 Jordan Aug. 11, 1942 2,417,195 Hargreaves Mar. 11, 1947 FOREIGN PATENTS Number Country Date 429,333 Great Britain May 28, 1935 

